It is well known that certain halo-2-pyridinyloxy compounds are useful as herbicides. Such compounds are prepared by a number of methods. For example, U.S. Pat. No. 3,814,774 teaches preparing a 3,5-dichloro-2-pyridinyloxyethyl hydrocarbon ether, ##STR1## where R is an aliphatic or aromatic radical by using a two-step process: (A) REACTING THE MONO ETHER OF ETHYLENE GLYCOL WITH AN ALKALI METAL HYDRIDE, SUCH AS SODIUM HYDRIDE IN AN INERT SOLVENT SUCH AS TETRAHYDROFURAN TO MAKE THE ALKALI METAL SALT OF THE MONO ETHER OF ETHYLENE GLYCOL, AND
(b) reacting this alkali metal salt with 2,3,5-trichloropyridine at about 50.degree. C. in the presence of a trace amount of copper powder to form the desired dichloropyridinyloxyethyl ether.
U.S. Pat. No. 3,862,952 teaches preparing 3,5,6-trichloro-2-pyridinyloxyacetic acid, ##STR2## by reacting 2,3,5,6-tetrachloropyridine with paraformaldehyde and an alkali-metal cyanide in an anhydrous water-miscible inert aprotic solvent (such as dimethyl sulfoxide or acetonitrile) to form 3,5,6-trichloro-2-pyridinyloxyacetonitrile, which is then converted to the desired product by aqueous acid hydrolysis.